Old English swæð, swaðu "track, footstep, trace, scar, vestige," from Proto-Germanic *swathan, *swatho (source also of Old Frisian swethe "boundary made by a scythe," Middle Dutch swade, Dutch zwade, German Schwad "a row of cut grass"); of uncertain origin. Meaning "a mown crop lying on the ground" is from early 14c.; that of "space covered by the single cut of a scythe" emerged late 15c., and that of "a strip, lengthwise extent" is from c. 1600.